For example as we age, natural levels of palmatoleic acid found in human sebum decline and these levels can be replenished with the palmatoleic acid in macadamia nuts for example. (austorganic.com)
The situation is that human sebum contains squalene in high concentrations, but when it oxidises and becomes squalene peroxide because of free radical attack, it's a nightmare for acne. (supernaturalacnetreatment.com)
Here is the composition of healthy human sebum: 12 % squalene, 41 % triglycerides, 26 % wax, and 16 % free fatty acids. (supernaturalacnetreatment.com)